title: A polymeric fastener can easily functionalize liposome surfaces with gadolinium for enhanced magnetic resonance imaging.
abstract: Common methods of loading magnetic resonance imaging (MRI) contrast agents into nanoparticles often suffer from challenges related to particle formation, complex chemical modification/purification steps, and reduced contrast efficiency. This study presents a simple, yet advanced process to address these issues by loading gadolinium, an MRI contrast agent, exclusively on a liposome surface using a polymeric fastener. The fastener, so named for its ability to physically link the two functional components together, consisted of chitosan substituted with diethylenetriaminepentaacetic acid (DTPA) to chelate gadolinium, as well as octadecyl chains to stabilize the modified chitosan on the liposome surface. The assembly strategy, mimicking the mechanisms by which viruses and proteins naturally anchor to a cell, provided greater T1 relaxivity than liposomes loaded with gadolinium in both the interior and outer leaflet. Gadolinium-coated liposomes were ultimately evaluated in vivo using murine ischemia models to highlight the diagnostic capability of the system. Taken together, this process decouples particle assembly and functionalization and, therefore, has considerable potential to enhance imaging quality while alleviating many of the difficulties associated with multifunctional particle fabrication.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
authors.forename: Cartney E
authors.initials: CE
authors.lastname: Smith
authors.forename: Artem
authors.initials: A
authors.lastname: Shkumatov
authors.forename: Sarah G
authors.initials: SG
authors.lastname: Withers
authors.forename: Binxia
authors.initials: B
authors.lastname: Yang
authors.forename: James F
authors.initials: JF
authors.lastname: Glockner
authors.forename: Sanjay
authors.initials: S
authors.lastname: Misra
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Roy
authors.forename: Chun-Ho
authors.initials: CH
authors.lastname: Wong
authors.forename: Steven C
authors.initials: SC
authors.lastname: Zimmerman
authors.forename: Hyunjoon
authors.initials: H
authors.lastname: Kong
mesh_terms: D000327:Adsorption; D000818:Animals; D002614:Chelating Agents / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D004369:Pentetic Acid / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D013816:Thermodynamics
chemical_list: D002614:Chelating Agents; D003287:Contrast Media; D008081:Liposomes; D011108:Polymers; D004369:Pentetic Acid; D048271:Chitosan; D005682:Gadolinium